Assume that a set of test scores is normally distributed with a mean of 70 and a standard deviation of 10. in what percentile is a score of 65?

30.85%

Step-by-step explanation:

Assume that a set of test scores is normally distributed with a mean of 70 and a standard deviation of 10

mean = 70 and SD= 10

To find percentile we use z-score value

z value can be find using formula

z=-0.5

Now we use z- score table to find the value when z=-0.5

P(x=65) = 0.3085

To find percentile we multiply by 100

0.3085 * 100 = 30.85%

add all the numbers and check the ones place.

the answer is 486. as the ones place is more than 4, the estimation will be the next 10 ie, 490